title: One-year outcomes of community-acquired and healthcare-associated pneumonia in the Veterans Affairs Healthcare System.
abstract: BACKGROUND
  While studies have demonstrated higher medium-term mortality for community-acquired pneumonia (CAP), mortality and costs have not been characterized for healthcare-associated pneumonia (HCAP) over a 1-year period.
  
  
  METHODS
  We conducted a retrospective cohort study to evaluate mortality rates and health system costs for patients with CAP or HCAP during initial hospitalization and for 1 year after hospital discharge. We selected 50 758 patients admitted to the Veterans Affairs (VA) healthcare system between October 2003 and May 2007. Main outcome measures included hospital, post-discharge, and cumulative mortality rates and cost during initial hospitalization and at 12 months following discharge.
  
  
  RESULTS
  Hospital and 1-year HCAP mortality were nearly twice that of CAP. HCAP was an independent predictor for hospital mortality (odds ratio (OR) 1.62, 95% confidence interval (CI) 1.49-1.76) and 1-year mortality (OR 1.99, 95% CI 1.87-2.11) when controlling for demographics, comorbidities, pneumonia severity, and factors associated with multidrug-resistant infection, including immune suppression, previous antibiotic treatment, and aspiration pneumonia. HCAP patients consistently had higher mortality in each stratum of the Charlson-Deyo-Quan comorbidity index. HCAP patients incurred significantly greater cost during the initial hospital stay and in the following 12 months. Demographics and comorbid conditions, particularly aspiration pneumonia, accounted for 19-33% of this difference.
  
  
  CONCLUSIONS
  HCAP represents a distinct category of pneumonia with particularly poor survival up to 1 year after hospital discharge. While comorbidities, pneumonia severity, and risk factors for multidrug-resistant infection may interact to produce even higher mortality compared to CAP, they alone do not explain the observed differences.
authors.affiliation: Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305-5236, USA. joehsu@stanford.edu
authors.forename: Joe L
authors.initials: JL
authors.lastname: Hsu
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Siroka
authors.forename: Mark W
authors.initials: MW
authors.lastname: Smith
authors.forename: Mark
authors.initials: M
authors.lastname: Holodniy
authors.forename: G Umberto
authors.initials: GU
authors.lastname: Meduri
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000191:economics / Q000453:epidemiology / Q000401:mortality*; D003428:Cross Infection / Q000188:drug therapy / Q000191:economics / Q000453:epidemiology / Q000401:mortality*; D003695:Delivery of Health Care; D005260:Female; D017048:Health Care Costs; D017052:Hospital Mortality; D006760:Hospitalization / Q000706:statistics & numerical data; D006787:Hospitals, Veterans / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010351:Patient Discharge; D011014:Pneumonia / Q000188:drug therapy / Q000191:economics / Q000453:epidemiology / Q000401:mortality*; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014481:United States; D014493:United States Department of Veterans Affairs
chemical_list: D000900:Anti-Bacterial Agents